Wedding season has arrived, which means that men everywhere will soon participate in a summer ritual as hallowed and time-honoured as marriage itself: sweating profusely. Most likely, they’ll have no one to blame but themselves, for they’ll have made the absurd decision to wear wool in the blazing sun.

For men who own just one suit, this is forgivable. With a mid-weight wool suit, in charcoal grey or navy blue, you’ll never be entirely out of place. But for grown-ups — men who own two, three or four suits — there’s no excuse for stocking a closet with styles that are perfect for November but otherwise not quite right. Canadians are blessed with four seasons; they should dress accordingly. In the depths of winter, hearty flannels and tweeds rule. Come summer, cotton is king.

That cotton out-cools wool should come as no surprise. “Think about it,” says my friend Sienna Pulati, who runs the London, England–based tailoring outfit The Fox and the Gentleman, “wool is sheeps’ natural insulator. Of course it’s warmer than cotton.”
Wool has tiny, natural crimps, which create small air pockets, making it an effective insulator. (The crimps also explain why it can itch.) By contrast, cotton’s smooth fibres mean it’s typically lighter, softer and more breathable than wool. Wool partisans may point out that Bedouins and Touaregs wear the fabric, but nomadic desert peoples prize versatility; the desert gets cold at night.

Still, cotton remains an unconventional summer suiting fabric. Perhaps this is because wool has long ruled in tailoring nerve centres like Italy and England, where the fabric’s resilience and elasticity, its sheen and its drape, came to define suits’ aesthetic. Cotton is particularly unpopular on Savile Row, where it’s perceived to offer poor value for money. (It’s true that a cotton suit is as labour-intensive and costly as wool, but not as durable.) Among her clients, Pulati says “many men shy away from cotton because it’s got a high crease factor. After a few hours, you end up with a much less pristine look.”

But the “crease factor” — caused by cotton’s inelasticity — is the key to its appeal. Pristine is overrated; good style requires nonchalance. A tasteful, meticulously tailored but slightly wrinkled suit indicates that you know the rules; you merely choose to ignore them. The same goes for cotton’s oft-maligned, flax-plant-based counterpart, linen, which looks best slim and rumpled. And whether you opt for a classic colour, like khaki or navy, or something bolder, cotton suits offer an adaptability that wool cannot: cotton lends itself well to spezzato — mismatching trousers and blazers.

If your primary objective this summer is blending in, stick with the four-season classic. You can sweat through your wool suit along with everyone else. I, however, will be wearing cotton — cool, comfortable, creased and, perhaps, just a tiny bit smug.